Prosthetic appliance



Nov. 26, 1963 J. w. BACH PROSTHETIC APPLIANCE 2 Sheets-Sheet 1 Filed Ma.y 19, 1961 Nov. 26, 1963 J. w. BACH paos'mrmc APPLIANCE Filed May 19. 1961 2 Sheets-Sheet 2 INV EN TOR.

Johann W. Bach W AGENT United States Patent O 3,111,683 PROSTHETIC APPLIANCE Johann W. Bach, Germaniaplatz 267, Essen-Borbeck, Germany Filed May 19, 1961, Ser. N0. 121,275 Claims priority, application Germany July S, 1960 12 Claims. (C1. 321) My present invention relates to a prosthetic appliance for artificial lirnbs, and more particularly to an artificial mernber (e.g. thigh or shank) forming part of such appliance.

Some artificial limbs at present in the market, designed to aflord a more flexible fit than those with rigid wooden or plastic sockets, are provided Witn leather sheaths or with padding usually made of foarn rubber; they have, however, the disadvantage of forrning an airtight con nection around the stump of the amputated extrernity, thus causing perspiration and often the appearance of boils and heat rashes. The blood circulation may also be disturbed by conventional appliances which are so rigid as to inhibit any rnovement of the sturnp muscles.

It is, therefore, an object of my present invention to provide an artificial limb mernber Whicl1 assures satisfactory ventilation of the stump.

lt is a further object of the present invention to provide a prosthetic member of suflicient elasticity to exert, during normal use, an invigorating massaging effect upon the stump and to stimulate its blood circulation.

It is another object of this invention to provide an artificial limb member of light weight and flexible construction resistant to wear and damage when in use.

A still further object of the present invention is to provide a prosthetic rnember whose length can be conveniently adjusted within certain limits.

In accordance With the feature of the present invention, the annular socket portion and the other, lower extremity (i.e. the part terminating in a knee or ankle) of the artificial member are interconnected by preferably outwardly arched spacer bars or staves er" streng elastic material, e.g. a light-weight metal such as aluminum or one of its alloys, prestressed to a certain extent by a series of flexible links holding the two extrernities together and surrounding the inserted stump so as to shield it from eontact With the spacer bars while affording access to the surrounding air.

According to a preferred embodiment of the present invention, the flexible links form a tubular array between two annular holders, one on the bottom part of the socket portion and one on the upper part of the lower portion The spacer bars are advantageously joined With the holders in a single sleeve-type unit integral With or suitably attached to the two extrernities.

The flexible links are preferably constituted by strands of metal or plastic inserted in protective sheaths at least 5 min. in diameter, so as not to cut into the tissue upon coming into eontact With the skin of the weare1. The elastic deformability of the spacer bars results in a light massaging of the stump when the appliance is put to its intended use. I prefer to employ as the links different portions of a single composite cable (or a small number of such cables) anchored to the holders and continuously wound back and forth between thern.

If either or each holder is adjustably mounted on the respeetive extremity of the prosthetic member, it may be reset frorn time to time to compensate for creep of the flexible link material (especially in the case cf plastic filaments) and/er to adapt the length of the member to the specific needs of the wearer.

The above and other features, advantages and objeets or" the invention will become more readily apparent from 3lllfl3 Palented Nov. 26, 1953 "ice the following detailed description, given in conjunction With the appended drawing in which:

FIG. 1 is an overall perspeetive view of a prosthetrc mernber according to the present invention, designed as a thigh prosthesis;

FIG. 2 is a longitudinal sectional view of the thigh prosthesis shown in FIG. 1;

FEG. 3 is a perspective view of the sleeve portion of the prosthesis of FIGS. 1 and 2, forming an intermediate unit between its extremities;

FIGS. 4 and 5 are respeetively a cross-sectional view and a longitudinal sectional view of the unit illustrated in FIG. 3; and

FIG. 6 shows a cross-section through the cable used in the unit of FIGS. 35, drawn to an enlarged scale.

As shown in FIGS. 1 and 2, the artificial limb comprises a socket portion 1, a sleeve 2 and a lower extremity 3. The soeket 1 is appropriately shaped to accommodate the upper part of the sturnp to be inserted through its outwardly flared upper end which may be additionally fastened to the body of the wearer by suitable means not illustrated. The lower extrernity 3 is upwardly concave and is externally split into sections traversed by a shaft 3a by which it can be hinged to a cornplementary part, not shown, of a knee joint whose structural details are not pertinent to the present invention. A shoulder 15 on the lower end of the socket portion 1 and a shoulder 15 on the upper edge of the lower extremity 3 support holder rings 5 and 6 Whieh are firmly cemented to these extremities, e.g. by an epoxy resin, or press-fitted to the shoulders. Removable annular shims 17 on the shoulders 15, 16 may be used to change the length of the artificial li1nb when necessary. The holder rings are spaced apart by staves 7, preferably made of metal, which are rigidly joined to the holder rings. The staves are bent outwardly and prestressed by a cable 4 Which, as shown in FIG. 2, passes back and forth between the rings 5 and 6 along their whole inner peripheries and is streehed to a certain extent to assure proper stressing of the barrelshaped sleeve unit 2 forrned by the rings 5 and 6 With the staves 7 and the cable 4. As shown in FIG.6, the cable 4 is constituted by filaments 8, preferably made of plastic, and protected by a flexible sheath 9, preferably also of plastic. The metallic portions 5, 6, 7 of sleeve 2 along With the external areas of the soeket portion 1 and the lower extremity 3 are proteeted by a flexible varnish or plastic coating 14.

The sleeve 2 is shown in greater detail in FIGS. 3, 4 and 5, in which the holder rings 5, 6 are shown spaced apart by four outwardly bent staves 7 fastened to the rings by rivets 18. The cable 4 is secured to the inner peripheries of the rings 5, 6 by threads 12 and 13. Thread 12 passes successively through each upper loop of the cable 4 and a Set of openings 11 in the upper holder ring 5, while thread 13 passes in a sirnilar manner successively through each lower loop of the cable 4 and a set of openings 10 in the lower holder ring 6. The slight spacing between the individual longitudinal reaches of the cable 4 assures a satisfactory Ventilation of the interior of the sleeve 2.

The length cf the artificial limb rnember, preset by the initial tension of the cable 4, may Vary 011 account of a sagging of the filaments 8 with resultant flattening of the staves 7 accornpanied by an increase in the distanee between the socket portion 1 and the lower extremity 3. T0 cornpensate for this change in length it rnay be necessary to withdraw either or both rings 5, 6 from their respective shoulders 15 16 and to remove as many of the shims 17 as is required, whereupon the seating areas of the holder rings will again be cernented o1 press-fitted to their respectrve extremities 1 and 3; in like manner additional shims may be inserted if lengthening of the lirnb is desired. The

3 staves 7 must, of course, be streng enough to support tl1e body weight of the an1prltee even in their most hignly flexed position without letting the end of the sturnp touch the hollowed-out limb portion 3.

Various modifications may suggest thernselves t0 those skilled in the art, especially With respect fo the connection of the holder rings With the staves 0r to the fastening 0f these rings to tl1e extremities 1 and 3, without departfrom the spirit of the present invention Within the scope of the appended clairns.

I claim:

1. In an artificial liinb for a prosthetic appliance, in cornbination, a pair of generally annular mernbers axially spaced apart, a subular array of flexible links interconnecting said rnembers linder tension, and a plnrality of curved resilient staves substantially more rigid than said links inserted at angularly spaced locations between saicl inks and firrnly secured t0 said members at opposite ends.

2. The cornbination according to clairn 1 wherein said links comprise at least one cable wound back and forth between said mernbers.

3. The cornbiriation according to claim 1 wherein said staves are bent outwardly beyond tl1e periphery of said array.

4. In a prosthetic appliance, in combination, a socket element adapted to receive a sturnp, and a sleeve body cornprising a pair of generally annular members axially spaced apart, a tubular array of flexible links interconnecting said members nnder tension, and a plurality of curved resilient staves substantially more rigid than said links inserted at angularly spaced locations between said links, one of said mernbers being rigiclly joined With said Socket element.

5. The combination according to clairn 4, further comprising anotl1er element forming an extremity opposite said socket element While being rigidly joined With the other of said mernbers.

6. The combination according 150 clairn 5 wherein s2iid elements are provided With generally annular shoulders surrounded by said mernbers, said staves being secured to said members externally of the latter.

7. The cornbination according to clairn 6, further comrising a protective outer coating extending over said elements and said staves.

8. In a prosthetic appliance, in combination, a socket element adapted to receive a stump, a sleeve bocly conr prising a pair of generally annular rnembers axially spaced apart, a tubular array 0f flexible links interconnecting said members under tension, and a plurality of curved resilient staves substantially more rigid than said links inserted at angnlarly spaced locations between said links, and means forming an adjustable connection between one of said members and said socket element.

9. In a prosthetic appliance, in cornbination, a socket element adapted to receive a stump, a sleeve body comprising a pair of generally annular members axially spacecl apart, a tubular array of flexible links interconnecting said members under tension, and a plurality of curvecl resilient staves substantially more rigid than said links inserted at angularly spaced locations between said links, anotner element forming an extremity opposite said socket element, first connection means rigidly joining one of said members Willi said socket element, and second connection means rigiclly joining the other of said mernbers With said other element, at least one of said connection means being acljustable.

10. T he cornbination according to claim 9 wherein said adjustable connection means includes removable spacer rneans between one of said mernbers and the associated element.

11. An artificial limb for a prosthetic appliance, comprising a pair 0f generally annular mernbers axially spaced apart, a plurality of curved resilient staves spacedly disposed about said members and joined thereto at respective ends, thereby forming a sleeve With lateral gaps, and flexible tie means anchored to said rnembers under tension and comprising at least one cable wound back and forth therebetween in a plurality of substantially parallel passes extencling Within each of said gaps in the direction 0f said staves, said tie rneans maintaining said staves Il!1dr flexural stress, said cable including a plurality of filaments and a common sheath enclosing said filaments.

12. A lirnb according to claim 11 wherein said filaments and said sheath consist of plastic material References Cited in the file of this patent UNITED STATES PATENTS 7,204 Yerger Mar. 19 1850 1,370299 Flanagan Mai. 1, 1921 2,229728 Eddels Jan. 28, 1941 

1. IN AN ARTIFICIAL LIMB FOR A PROSTHETIC APPLIANCE, IN COMBINATION, A PAIR OF GENERALLY ANNULAR MEMBERS AXIALLY SPACED APART, A SUBULAR ARRAY OF FLEXIBLE LINKS INTERCONNECTING SAID MEMBERS UNDER TENSION, AND A PLURALITY OF CURVED RESILIENT STAVES SUBSTANTIALLY MORE RIGID THAN SAID LINKS INSERTED AT ANGULARLY SPACED LOCATIONS BETWEEN SAID LINKS AND FIRMLY SECURED TO SAID MEMBERS AT OPPOSITE ENDS. 